The Government is also facing a rebellion on another front from pro-European Tory MPs who want to see the UK stay in the Customs Union.

When Mr Davis quit last Sunday night in a shock resignation he said that Mrs May’s Chequers compromise would leave the UK in a “weak negotiating position”.

In Mr Davis’s official resignation letter, he said: “The national interest requires a Secretary of State in my department that is an enthusiastic believer in your approach, and not merely a reluctant conscript.